Why imparfait in the si clause?

Question

In a sentence with a main clause and a si clause, the first uses the conditionell and the second the imparfait. For example, Je partirais si j'avais une voiture. Would it not make more sense to use the conditionelle for the si clause as well? After all, it also expresses a hypothetical situation. Why the different modes in the main clause and the si clause?

Cécile Janty-Davies · Accepted Answer

Hi Bert, 
I am afraid it is very wrong in French and often used as an example of bad French by comics :
Si j'aurais su, j'aurais pas v'nu = If I had known, I wouldn't have come
below spoken by a child in a well-known film -
https://jaimelesmots.com/ben-mon-vieux-si-jaurais-su-jaurais-pas-vnu/
As to why it's just the way it is, I believe it is the same in English, but am prepared to be corrected if I am wrong.

Bert Gordijn · Answer

Thanks Cécile!

Chris Wirt · Answer

Cécil is correct: conditional sentences are one of the few instances that follow the same pattern in English and French.If I knew, I would tell you. -- Si je le savais, je te dirais.